Alright...I've reached 2 hearts with Nick.....why hasn't he given me his Sunstone yet? I'm buying food from him and learning new recipes every time I go to the diner...still, nothing happened! Maybe the amount of affection points just hasn't reached 7,000 yet...HURRY UP ALREADY!!!!
If I remember correctly, characters'll hit two hearts before they actually have the required friendship points.
If he's at two hearts, it shouldn't be long, though. Just keep buying things from him every day, and he should hit the required points soon.